Earth Sciences and Ecology Question #313

The answer

"It is because we all came from the sea and it is an interesting biological fact that all of us have in our veins the exact same percentage of salt in our blood exists in the ocean and therefore we have salt in our blood, in our sweat, in our tears. We are tied to the ocean and when we go back to the sea, whether it is to sail or to watch it, we are going back to which we came." - President J. F. Kennedy, To Be or Not To Be

The percentage of salt in seawater is called "salinity."

Salinity is defined as the total amount of solid matter dissolved in a kilogram of seawater -- not including organic matter -- in parts per thousand